1. Technical Field
The present invention relates in general to graphical user interfaces and in particular, to graphical user interface elements such as scrollbars. The present invention also relates to graphical pointing devices. More particularly, the present invention relates to trackpoint-type pointing devices. Still more particularly, the present invention relates to methods and systems for managing graphical pointing devices utilized in association with scrollbars displayed within graphical user interfaces.
2. Description of the Related Art
A graphical user interface is a type of display format which enables a user to choose commands, start programs, and see lists of files, objects and other options by pointing to pictorial representations and lists of menu items on a computer display screen. Choices can generally be activated by either a keyboard or a pointing device such as a mouse. A mouse is a commonly utilized pointing device, containing one or more buttons, that allows a user to interact with a product or operating environment through an associated graphical user interface.
Some conventional graphical user interfaces provide a cursor and scroll bar for scrolling through portions of a viewable object. A viewable object is an object that is the focus of a user's attention. A viewable object can contain multiple components such as spreadsheets, text, hotlinks, pictures, sound, and video objects. However, a viewable object is not limited to these components. In many types of graphical user interfaces, a vertical or horizontal bar at the side or bottom of a graphical user interface window can be utilized in conjunction with a pointing device such as a mouse, trackball, or stylus to move about in a viewable object. Scrolling permits viewing of any desired portion of a viewable object and is so named because it is the electronic equivalent of reading through a rolled (i.e., scrolled) viewable object rather than flipping through pages of a book. A vertical scroll bar is usually utilized to control up and down movement (e.g., through lines and pages of a viewable object), while a horizontal scroll bar controls movement across a viewable object.
Scrollbars are thus common graphical elements utilized in personal computer user interfaces (i.e., graphical user interfaces). A scrollbar adjusts a value along a range of possible values. Such scrollbars can be utilized to scroll a picture left or right on a display screen, or to adjust the color of an area on the screen, depending on the particular application to which the scrollbar is dedicated. Scrollbars are typically operated with a mouse or other pointing device. A user can utilize a pointing device to point a displayed cursor at the scrollbar, and then utilize a selection button displayed within the graphical user interface to manipulate the scrollbar via a so-called "click" of the pointing device. Many scrollbars include associated arrows for controlling the scrollbar. In some scrollbar applications, the user can click on a left arrow to decrease a value (i.e., numerical position or coordinates) by a small amount. If the user clicks on the arrow and holds down the pointing device button, then the value will continue decreasing until the button is released. Similarly, a right arrow can increase the value. The slider thus moves left and right as the value changes, in response to user input directed from the pointing device.
Scrollbars have several advantages. Scrollbars allow small, discrete increments and decrements to a value by "clicking" on arrows associated with the scrollbar. Scrollbars can also direct manipulation of a value by dragging the slider back and forth (or up and down depending on whether a user is dealing with a horizontally or vertically displayed scrollbar). Another important advantage associated with scrollbars is that such graphical elements display the current level of a value based on the position of the slider. Thus, scrollbars provide a visual indication of the status as well the means by which to alter the position of the slider.
An example of a pointing device which utilizes scrollbars to manipulate pictures or objects displayed within a graphical user interface is the IBM TrackPoint II.TM.. The IBM TrackPoint II.TM. is a product of International Business Machines Corporation, located in Armonk, N.Y. The IBM TrackPoint II.TM. pointing device is commonly available on IBM ThinkPad.TM. products, which are also products of International Business Machines Corporation. This pointing device is composed of a lever located within a keyboard sych that the lever drives a mouse pointer about a display screen. Selection buttons correspond to mouse buttons. The buttons and the lever may be utilized in combination by the user so that the user can manipulate objects displayed on the display screen.
Several problems are associated with such pointing devices. One problem associated with such pointing devices is that it is more often difficult to "drag" an object utilizing such a pointing device than dragging an object with a mouse. If the selection button is separated from the lever, the user must hold the button and manipulate the lever simultaneously. This requires increased dexterity on the part of the user than simpler operations associated with a mouse, because the lever button and the selection button are two separate objects. Moreover, if the button is built into the TrackPoint lever, it may be mechanically impossible to perform a dragging operation. Even with a mouse, however, the technique of dragging is still difficult for many people to perform particularly beginning computer users.
Another problem associated with such pointing devices is that if the user "clicks" a side arrow and moves too far in a single direction, it is often difficult to switch directions. The user must switch from the selection button to the lever, move the pointer to the other arrow, and then switch back to the selection button, a time-consuming and difficult task. In some situations, an extreme level can result in serious problems. For example, in graphical user interfaces that display "audio" button controls based on sliders, if a user accidentally raises the volume too high, damage to equipment and human ears can occur while the user fumbles to turn the volume down. Thus, in many contexts, dragging a scrollbar slider is more appropriate than utilizing arrows associated with the scrollbars. However, many pointing devices, such as those described herein are simply not suitable for dragging.
Based on the foregoing, it can be appreciated that a need exists for a method and system in a graphical user interface which would allow a user to continue to use pointing devices while avoiding problems associated with scrollbars and such pointing devices.